As was discussed earlier, there are always exceptions, and exceptional people. But they are not the norm.

Keep in mind that the kicks we practice in the p/k arts today -- wheel kicks, spinning back kicks, all of the jumping high kicks -- are contemporary in making. They were not a part of classical self-defense or combat arts, even though they might have been kept as an "artsy" extra in some of the old Chinese arts that had moved into the realm of performance or spiritual art and away from street "practical" combat. TKD, "Home of the High Kicks" is a modern art that was cobbled together from Shotokan karate and (apocryphal) vestiges of Korean leg-fighting and kicking systems that were alleged to have been practiced as sport, and for entertainment in the royal court -- not the battle field or street.

In short, these kicks are meant to be performed against other kickers, and the fighting strategies that most people practice in their schools are designed with other kickers in mind. That's how most people spart, in other words. Even most "self-defense" routines seldom start with a high, spinning or flying kick; they are mainly a "finishing-off" technique after the "bad guy" has been incapacitated with strikes, punches or other less vulnerable actions.

Unless you train with grapplers who, in the skills of their arts, are equal or superior to your skill in your kicking art, you will not learn how to make high kicks work effectively against a good or superior grappler.

That was my "beef" after training in TKD and karate, as well as "external" Chinese arts, for many years; we trained only against our own system and its stylized methods. To obtain an understanding of the limitations of this type of training, I ultimately had to leave and take up grappling/jujutsu and MMA. The experience clarified, nearly immediately, both the weaknesses and potential strengths of high kicks are.